Conventionally, dehumidification systems each configured to supply dehumidified air to the inside of a room have been known. Patent Documents 1 and 2 disclose the dehumidification systems of this type.
Patent Documents 1 and 2 describe the configuration in which, in an air passage, three adsorption rotors are arranged in series and in three stages. The air passage includes an air supply passage for supplying outdoor air processed by the adsorption rotors to the inside of the room, and an air discharge passage for discharging indoor air to the outside of the room. Each adsorption rotor is disposed so as to extend over both of the air supply passage and the air discharge passage, and is rotatable about a rotary shaft interposed between the air supply passage and the air discharge passage.
The adsorption rotor is configured such that moisture contained in air flowing through the air supply passage adsorbs onto the adsorption rotor and therefore the air is dehumidified. Moreover, the adsorption rotor is configured to be recovered by dissipating moisture to air flowing through the air discharge passage. In the air discharge passage, an air heater configured to heat air is provided so that the heated air can be used for recovery of the adsorption rotor. When the amount of moisture adsorbing onto part of the adsorption rotor increases, the adsorption rotor rotates to move such a part to the air discharge passage. After the adsorption rotor is recovered by dissipating the moisture, the adsorption rotor is re-used for adsorption. According to the foregoing configuration, low-humidity air flowing through an air passage for adsorption is continuously supplied to the inside of a room, and dehumidifies the inside of the room. Moreover, heated indoor air is used for recovery of the adsorption rotor, and then is discharged to the outside of the room.
Since outdoor air passes through the adsorption rotor three times, air supplied to the inside of the room has a low dew point, and therefore can be used as air (i.e., air having a dew point of about −50° C.) supplied to, e.g., a dry clean room where lithium-ion batteries are manufactured. In the system of this type, it is often the case that the adsorption rotors are arranged in two stages.